Music plays only one side of the headphones?

I have tried multiple headphones, but I can only hear the music on one side of the headphones; so, the problem isn't the headphones, it is the ipod touch itself. If I plug the headphones in all the way, it only plays on one side, and if I just barely plug it in- just touch the output, then it plays on both sides. But, it has become incredibly difficult for me to listen to the songs with the headphones plugged in all the way, and its way too hard to listen to it, carefully keeping watch for the positioning of the wire. Please help me fix this problem, so that I too can completely take advantage of the Ipod Touch. It has only been a year, and this ipod has gone wrong within less than a year after purchase. Hope the description helps solve my problem.